First AR build

I was bored in the store yesterday, so I figured I would make an attempt at building myself an AR lower.
The lower is Spikes tactical, the parts kit is Stag arms, and the buffer, tube, spring and stock are Tapco.
I will post pics when I can. This is the first time i've attemted to assemble an AR, so i'm pretty stoked
I've got my completed lower on layaway, I should be able to pay it off in two weeks. Then I need to find an upper.
My boss told me I should be able to build a basic M4 carbine for between $650 and $700. Only problem is, parts suppliers like Brownells want that price just for a complete upper.
If the price goes a little over 700, thats okay, but I want to keep cost at a minimum while still using quality parts.
So, do you guys think I should do like Johnny Cash and get it "one piece at a time"? or just save up and get a complete upper and barrel?
I'm also looking for suggestions as to the brand of parts I need, and a good place to get them.

I was bored in the store yesterday, so I figured I would make an attempt at building myself an AR lower.
The lower is Spikes tactical, the parts kit is Stag arms, and the buffer, tube, spring and stock are Tapco.
I will post pics when I can. This is the first time i've attemted to assemble an AR, so i'm pretty stoked
I've got my completed lower on layaway, I should be able to pay it off in two weeks. Then I need to find an upper.
My boss told me I should be able to build a basic M4 carbine for between $650 and $700. Only problem is, parts suppliers like Brownells want that price just for a complete upper.
If the price goes a little over 700, thats okay, but I want to keep cost at a minimum while still using quality parts.
So, do you guys think I should do like Johnny Cash and get it "one piece at a time"? or just save up and get a complete upper and barrel?
I'm also looking for suggestions as to the brand of parts I need, and a good place to get them.

Sorry I missed this the first time around.

So, are you asking if you should just buy a completed upper? Or buy parts piece meal as you go along?

I would definitely recommend buying individual parts and assembling them yourself.

But you aren't going to build an M4ery in this market for $650 or $700. More like $900. It's the market right now. 2 years ago, that would been very do able, but now, not so much....

Got a quick ? I have DPMS Ar chambered in 223/5.56 and am wanting to go bigger can I use my existing lower and of coarse a new upper for 6.5 creedmoor??? The bullets are almost the same length just the 6.5 is fatter so I need to know whether I can use my lower with the right upper????

I recently finished building this for around $1500. Take away the quad-rail, red dot sight, magnifier, grippod and angled foregrip, the cost is more like $900-$1000. That's Stripped Lower and lower build kit, Complete upper and Troy/Spikes Rear Battlesight for around $900. With no mags or ammo.